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Two Snowflakes May Be Alike After All
An anonymous reader writes "LiveScience is reporting that it may be possible for two snowflakes to be alike after all. For anyone who studies probability, this seems reasonable, given that the article mentions that 10^24 snowflakes fall in any given year. The article contains links to fascinating snowflake pictures. From the article: 'A typical snow crystal weighs roughly one millionth of a gram. This means a cubic foot of snow can contain roughly one billion crystals ... "It is probably safe to say that the possible number of snow crystal shapes exceeds the estimated number of atoms in the known universe," Nelson said. Still, while "no two snowflakes are alike" might hold true for larger snowflakes, Nelson figures it might ring false for smaller crystals that sometimes fall before they have a chance to fully develop. "How likely is it that two snowflakes are alike? Very likely if we define alike to mean that we would have trouble distinguishing them under a microscope and if we include the crystals that hardly develop beyond the prism stage--that is, the smallest snow crystals," Nelson said.'"
"It is probably safe to say that the possible number of snow crystal shapes exceeds the estimated number of atoms in the known universe..."
This sort of thing does my head in. Anyone else trying to keep up?
'Thats they exact same thing a banana wrench monkey.'
...and of course, I can't find it... a scientist published a picture of two identical snowflakes in, I'm almost sure, Science or Nature. And, no, I'm not talking about Snowflake Bentley. It was a byproduct of some kind of meteorological research, they were flying a plane through clouds where snow was being formed, and, as you'd expect, if two flakes of snow form under virtually identical conditions you end up with two virtually identical flakes.
I think this was in the 1990s.
It made the mainstream news at the time.
"How to Do Nothing," kids activities, back in print!
What goes up must come down. (suspected true)
Lightning doesn't strike the same spot twice. (obviously false (ouch!))
A watched pot never boils. etc...
This is like numerology. You take a bunch of squishy data (aphorisms) and attempt to rigorously evaluate them.
I am reminded of Charlie Brown's answer to the question "How many angels can dance on the head of a pin?" His answer: Eight if they're skinny, four if they're fat.
Don't trust anyone under thirty.
As stupid as it sounds, original submission is entirely redundant, as one scientist already found matching snowflakes. And the scientist wasn't even a guy but a woman scientist. Yes, Virginia, there really is serious study on the shapes of snowflakes.
Typically I eat snow by sticking my tongue out, not by eating what's on the ground, so I'd be a little surprised (and worried) to find a yellow snowflake flying through the air. I try not to stand under animals pissing from trees when I eat my snowflakes.
No existe.
What goes up must come down. (suspected true)
Oh yeah... tell that to Voyager. Lightning doesn't strike the same spot twice. (obviously false (ouch!)) Well after lightning strikes the first time, that place (ouch) is never going to be the same again.A watched pot never boils. etc...
There's actually some truth to that... If you take the lid of a pot that you're trying to boil, the escaping steam carries away heat and helps to cool the pot -- It also lowers the vapour pressure of the steam, which allows more steam to be generated (allowing the water in the pot to cool faster).That way, a watched pot boils a lot slower than an unwatched pot -- and if the heat is low enough, then removing the lid actually will make the differnce between boiling, and just evaporating at a high temperature.
This message brought to you by the society for the anal retentive (I had to say that, or they'd browbeat me to death).
Sometimes boldness is in fashion. Sometimes only the brave will be bold.
Another one is the belief that the rifling pattern engraved on a fired bullet can be used to positively identify the gun from which it was fired. This assumption rests in turn on the assumption that no two gun barrels are exactly alike. How do we know?
These two examples are a bit more serious than the case of snowflakes, because they're used as evidence in criminal trials. I suppose there must be scientific, peer-reviewed studies out there somewhere about the uniqueness of fingerprints and rifle barrels. But I don't see how they could do any more than establish the probabilities of any two of these objects being sufficiently alike as to be practically indistinguishable. I'd sure like to know what these probabilities are...they're certainly never mentioned in a courtroom.
DNA matching is probably on firmer ground, right?
Great men are almost always bad men--Lord Acton's Corollary